Controlled communication circuit



May 3o, 1933. w. o. MILLER 1,911,706

CONTROLLED COMMUNICATION CIRCUIT Filed July 30, 1932 3 Sheets-Sheet l A Inventor 0. Mz'ZPiM liomey `May 3.0, 1933. w. o. MILLER 1,911,706

I CONTROLLED COMMUNICATION CIRCUIT Filed July so, 1932 :sheets-sheet 2 Inventor ,/qllmey Albin-fil 1r. am'izlrf May 30, 1933- w70. MILLER 1,911,706

CONTROLLED COMMUNICATION CIRCUIT y Inventor .22T 0. 7)1 Zie rfvllomey Patented May 30, 1933 vra'rsu'r otros WILLIAIHI 0. MILLERLOF SACRAMENTO, CALIFORNIA CONTROLLED CGIJMNICTION CIRCUIT Application filed July 3),

4My invention relates to controlled communication circuits, and an important object of my invention is to provide control means for such circuits which operate di- 5 rectly from commercial alternating power supply, and eliminate the necessity for local direct current supply means.

` In control means for this type ofcircuits in use at the present time, either a separate control wire is necessary between the stations in the circuit, or a distinct local battery or generator-battery direct cu ren supply means is required for the operation of the circuits in each station, with consequent large expense for operation and maintenance, and the liability to lbreak downs, besides other disadvantages and diiliculties well recognized by those who have to do with thedesigning, installation, operation, and maintea nance of such stations and circuits.

The invention comprises means ,for eliminating all or the greater part of such ez;- penses and disadvantages and inconveniences, by eliminating the necessity for an entra control wire, and the direct current supplying means for each individualV station, besides other features which will appear below.

Other objects and advantages of my invention will be apparent from a reading of the following description in connection with the drawings, wherein Jfor purposes of illustration I have shown preferred embodiments of my invention.

In the drawings Figure l is a diagrammatic representation ottheapparatus and electrical connections of a pair of stations, in which rectifier mean is utilized in aone wire circuit.

Figure 2 is a diagrammatic representation of the apparatus and electrical connections of a station circuit utilizing a two-wire or loop circuit, one portion at the left being a control or switching station from which asubscriber station illustrated atv the right of the drawing may be switched to another station or connected to a telegraph repeater or carrier system.

' 'Figure 3 is a diagrammatic representation ofthe embodiment of the invention illustra*- rss2. serial no. esame. Y

ed in Figure 2 showing the same operated upon a single wire. v

The various apparatus employed by me in the embodiments shown herein are of standard type and constructionand selected for :f

their special dutiesaccording to capacity and the 'electrical e'ectiveness. Therefore, each or' the apparatusv will not be described in detail, as this is believed to be unnecessary to acquaint persons familiar with this art with the nature and arrangement and construction of the various embodiments of the invention.

Referring in detail to the drawings, and

particularly to Figure 1, it will be observed that the left hand group, representing a station is designated A, while thegroup tothe right representing a companion station is generally designated by the letter B. Gom- ,f

ticularly adapted to use in controlling telegraph and teletype printer circuits, for open s and close, or make and break operation, by means of which both signal and control arrangements are obtained without the use of direct current local supply means for the operation of the various relays, such as is usually required for this purpose. The direct current which I utilize in .the embodiments is converted or generated automatif cally Jfrom commercial alternating current supply as 'a result ofmomentarily sho'rting the start contacts of a relay by operating the st art key, which start key is placed in the alternating currentV supply in such a manner that it closes a circuit lto avrectiiier Jfor an instant, or for as long as itis required' to buildup sufiicient direct current from the rectifier to cause a current to flow through the circuit.

In the embodiment shown inl Figure 1 in eachstation A, B the start key is generally designated by the numeral 5, while the rectifier is designated in the drawings. The direct current thus produced Hows through resistance 6 to the stop contact 7, then through the relay 8 to the ground 9, thereby operating the relay 8 so that the relay contacts act as a switch for the rectifier. The rectifier thus connected, the produced direct current will then flow from the rectifier through the resistance 10, through the relay coil 11 to the ground 12, thereby transferring the armature 13 of the relay 11 to its :iront contact which is connected to the set 14. This results in closing a circuit from the rectiier through resistance 15, through the set 14 to the single line 16 connected to the armature of the relay 11 in the circuit B.

In the circuit B, the current coming over the line 16 passes through the armature 13a to the stop contact 7 a, through the relay 8a to the ground 9a, thereby operating relay 8a which in the manner already described, closes thealternating current supplyv to the rectiiier whereby there is produced a direct current vwhich Hows via resistance 6a, and through resistance 10a, thence through the coil of the relays 11a and 8a through the grounds 12a and 9a, respectively, thereby causing these relays to operate simultaneously, holding them in their operated dispositions. The sets are now closed for operation between station A and station B, the time required to close the circuit as outlined above being about one second.

' The station sets 14 and 14a may be closed down and released from the alternating current supply after conclusion of a business period by operating the'respective stop contacts 7- at each station simultaneously. If a tele'type simplex printer is used in the circuit, the stop feature may be employed for stopping the sets by means of a synchronized impulse sent over the line and circuits.

Referenceis now made to that embodiment of the invention which is shown in Figure 2. This embodiment comprises means for operating lover a loop circuit. In Figure 2, station A is predicated as a control or switching station, from which station B, a subscriber, may be switched to another station or connected to a telegraph repeater or carrier system for long haul connections. In this embodiment also standard parts and connections are arranged according to the principles of the invention. The operation thereof as explained below will also teach the arrangement and connection of the various apparatus constituting the embodiment When the operators set 20 is connected into the jack 21, current will iiow over the tip side 22 of the loop or paired armature 24of relay coil 25, through the stop contact 26, thence through the winding of the relay27 to the ground 28, thereby operating and closing relay 27 which thereby acts as a switch to close a circuit from the alternating current supply to the rectifier so as to produce and build up instantaneously a direct current which flows via resistances 29 and 30, thence through/ the winding of the relays 25 and 27, thereby holding relay 27 which has been operated to its closed position, at the same time closing the relay 25, which operates to connect the printer magnet 31 and its associated sending contacts 32 in series with the tip side 22 and the ring 33 of the loop. These operations and connections made, station B will be in a position to transmit to station A preparatory to being connected through the agency of station A to another station, or to a repeater. After such connection has been made,the entire circuit may be restored to its normal position simply by ,operating the stop contacts at both ends simultaneously.

Station B may originate a calll and signal the station A by momentarily operating the start button or key 34 whereby'to short the contacts of the relay- 27 for energizing the rectifier for producing and building up in- U stantly a direct current which closes the relays 25 and 27 through the resistances 29 and 30. As the armature of the relay 25 has closed to its inner contact, the printer magnet 31Y and the sending contacts 32 are connected across the loop. In this disposition current will flow from the battery 35 (not shown) of station A to the ring side 33 via upper Contact of the jack 21 over the line to the station B through the printer magnet 31, the sending contacts 32 andback again on the tip side of the loop through the lower Contact of the jack 21, and through relay 26 to ground;

As a result relay 26 is operated and closes the circuit and lights the lamp 37 thereby signalit ing the operator at station A, who then inserts the plug of set 2O into the jack 21, extinguishing the lamp 37 and supplying battery for operation of the line. A and B are then in communication.v j

Reference is now made to Figure 3 of the drawings which illustrates a manner of connecting the apparatus and circuits shown and described with respect to Figure 2,in a single line arrangement instead ofthe looparrangement of Figure 2. Numerals from 40 up` wards designate various elements of this third embodiment of the invention. The connections will be obvious from the following description of the operation thereof. Placing the apparatus set plug 40 into they jack 41 will cause a negative current to flow through the single line 42 to the armature 43 of relay coil 44. through the stop contact 45, through the winding of' relay 46 to the ground 47, thereby operating the relay 46 closed so as to close the circuit from the operating current supply to the rectifier for producing and building up a direct Vcurrent iiow through relays 46 and 44, respectively, and holding them closed The stations through the resistances 48 and 49 thereby transferring the armature 43 of relay 44 to its front contact whereby to connect the printer magnet 50 and sending contacts 51, and connect the printer magnet 50 through the inner contact and armature of relay 44 and carry over the line 42 to the negative battery 52 at station A. The operators set is designated 58. The circuit is now closed for in connection with the well known teletype simplex printer used extensively by commercial telegraph companies using small motor-generator sets and rectiiiers in stations which do not warrant the installation of eX- pensive constantly operated power plants, which are usually found in the Ylarger cities. These arrangements would be replaced by the invention as is evident.

Teletype simplex printer systems, usually installed in a customers place of business, and are usually remote controlled from the main oflice over an additional Wire connected through relays provided for this lpurpose through some source of direct current, usually a rectifier or a motor-generator set which is continuously operated from the commercial alternating current, or through some source of direct current supplied from the main oflice storage batteries. The savings in expense for building, operating and maintaining communication lines of this nature, which are provided by the utilization of the invention, are believed to be evident.

Though I have shown and described herein preferred embodiments of the invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in material and structure and arrangement of parts, within the spirit of the invention and the scope of the subjoined claims.

It will be evident that utilizing the device of the invention, it would not be necessary to constantly supply the stations with operating current, but the economical convenience is brought about by the invention that the current is supplied and consumed to the stations only during the restricted operating periods thereof. 1

That is claimed as new is l. Control circuits for electrical communication circuits having a communication line comprising alternating current input means,

" a relay interposed in the alternating current input means, rectifier contacts operated by the relay, a current rectifier connectible with thealternating current input means by said relay, start keymeans for conditioning the operation of the relay, and stop means in circuit with the winding of the relay and with the communication line, an operators set in circuit with the rectifier, and a relay operated by the rectifier, a two point contact arrangement for the armature of the second mentioned relay, the armature being connected directly in the conununication line, whereby said start means and stop means is capable of conditioning the operation or inoperativeness of a companion similar station to which said communication line is connected. v

2. Control circuits tor electrical communication circuits having a communication line comprising alternating current input means, a relay interposed in the alternating current input means, rectifier contacts operated by the relay, a current rectitier connectible with the alternating current input means by said relay, start key means for conditioning the operation of the relay, and stop means in circuit with the Winding of the relay and with the communication line, an operators set in circuit with the rectifier, and a relay operated by the rectilier, a. two point contact arrangement for the armature of the second mentioned relay, the armature being co'nnected directly in the communication line, whereby said start means and stop means is capable of conditioningthe operation or inoperativeness of a companion similar station to which said communication line is connected together with switching means comprised in a separate station utilized for station selection, said switching means comprising an operators set battery operated, a tip and ring equipped jack to be contacted thereby, a relay controlled thereby, and a signal operated by the relays, the tip and ring conductors of the jack being connected with one of a plurality of stations to be controlled, for controlling, starting and stopping communications therewith. n

3. A single wire circuit :tor controlling a plurality of stations of the type described comprising a battery-operated operators set including a jack and return signal means, a single communication wire to a station, said station comprising printing magnet means, sending contacts, relays for conditioning the operation of the printing magnet means and sending contacts, and relay means for connecting the same to a source of alternating current supply, a rectiiier interpolated between the alternating current supply and the same, and start and stop means for conditioning the operative connection of the rectifier and for reversing a call to the station.

In testimony whereof I aiiix my signature.

' WILLIAM O. MILLER. 

